The present invention relates to remotely managed network systems, in particular to a remotely managed packet data system having control information provided during non-data gaps between the data packets.
Prior control of remote network system devices, such as by SNMP control, have eaten into the bandwidth available for data and other network traffic. Moreover, the management and signalling protocol for such remotely-managed network devices have been excessively cumbersome, unstable or otherwise undesirable. Such protocol control of remote devices require the same high-level network operations as required for the data exchange, and may also fail to provide available network management when the system high-level network operations becomes disabled.
The apparatus and system according to the present invention provides a Wan Management channel via xe2x80x9cquasi-in-band signallingxe2x80x9d to control remote network devices by physical layer interface devices having programmable access to the signal bits presented during the idle period which are added after packet-based network data (e.g. Ethernet) encoding and removed before network data decoding to remain transparent to normal system data transfer operation and bandwidth availability.
The system according to the present invention operates the remote devices in a stateless mode, wherein responses to received commands result in a direct remote device response, thus avoiding unstable and unpredictable system operations, especially during start-up or other transient conditions. Moreover, the added network control data signalling added does not reduce system reliability, but provides network control of enhanced reliability since the WAN management signal, being included in a data format significantly shorter than the prior network data packets, is less likely to be corrupted and thus more likely to be transferred without error.
Furthermore, the devices and system according to the present invention provide serial nesting of such remote devices along the Ethernet path, with the instructions to and data from each such remote device(s) forwarded through intermediate remote device(s) by successive receipt and retransmissions, or xe2x80x9chopsxe2x80x9d according to the present invention.